The present invention relates to a metal collar mounted in a resin component and to a mounting method therefor. More specifically, the present invention relates to a metal collar able to be mounted easily without using a press machine when the metal collar is mounted in a resin component to prevent deformation of and/or damage to the resin component, and to a mounting method therefor.
Often, when a resin component is fastened on a mounted member using a bolt, the fastening force of the bolt in the axial direction deforms, damages, or cracks the resin component. In order to prevent deformation of and/or damage to the resin component, a metal collar is fitted inside a through-hole used to fasten the resin component, and the resin component is fastened to the mounted member with a bolt via the metal collar. The metal collar can be mounted by integrating the metal collar when the resin component is molded, or by attaching the metal collar after the resin component has been molded. In the case of the latter, when the metal collar is attached after the resin component has been molded, the metal collar is inserted into a through-hole in the resin component to keep the metal collar from coming off the resin component. Afterwards, the metal collar is often deformed. The metal collar is sometimes deformed when the metal collar is forcibly crimped in the axial direction using a press machine.
However, when the metal collar is deformed using a press machine and the resin component is larger, the mounting operation is difficult to perform. As a result, a large press machine is required. Also, when the resin component has an intricate shape, it is difficult to mount a metal collar using a press machine. Also, the metal collar mounting operation is limited to locations where a press machine can be found.
A structure is disclosed in Japanese Published Unexamined Utility Model Application No. 6-58217U (Patent Document 1) in which a synthetic resin panel is fastened to a fixed member using a nut and bolt. In Patent Document 1, the structure has a flange abutting a surface of the synthetic resin panel on one end, and a metal sleeve passing through a bolt hole in the synthetic resin panel. A slit is provided in the leading end of the metal sleeve, and pressure is applied to the leading end to expand and buckle the leading end into a petal shape, which forms a spring washer portion. The synthetic resin panel is interposed between the spring washer portion and the flange. The spring washer portion is interposed between the synthetic resin panel and the fixed member. A bolt is passed through the metal sleeve and the bolt hole in the fixed member, and the bolt is fastened using a nut. In Patent Document 1, excessive fastening force is absorbed by the spring washer portion, and the synthetic resin panel can be fastened without damage. However, in Patent Document 1, because the leading end of the metal sleeve is pressed by a pressing tool to buckle and deform the leading end, it is difficult to use this structure in a press machine.
In Japanese Published Unexamined Patent Application No. 11-101218A (Patent Document 2), the metal collar has a cylindrical tubular portion and a flange portion at the base end. A counter bore is provided on the upper edge of the through-hole in the resin component, and a recess is provided on the lower edge of the through-hole to receive the flange portion. After the metal collar has been inserted into the through-hole, the leading end is pressed to buckle the buckled portion into a wedge shape. The resin component in which the metal collar has been fitted is fastened to a mounted member using a bolt via a washer. In Patent Document 2, the metal collar is prevented from coming out of the through-hole in the resin component, and the buckled portion of the metal collar prevents loosening of the fastened member. However, in Patent Document 2, it is difficult to press this metal collar with a press machine.
In Japanese Published Unexamined Patent Application No. 6-10930A (Patent Document 3), a large-diameter flange portion is formed at one end of a nut and a thin portion is formed at the end opposite that of the flange portion. After the nut has been fitted in an engagement hole in a resin frame, the thin portion of the nut is forcibly crimped in the counter bore portion of the resin frame, and the nut is engaged with the resin frame. Because the thin portion is easily deformed, it can be easily crimped. However, in Patent Document 3, the thin portion of the nut is forcibly crimped using a crimping tool. As in Patent Document 1 and Patent Document 2, it is difficult to press using a press machine.
Thus, a metal collar that can be quickly and easily mounted in a resin component is desired. A method for mounting a metal collar quickly and easily in a resin component without using a press machine is also desired. A method to easily mount a metal collar in a resin component having an intricate shape or large shape is also desired. A method for mounting a metal collar that is not limited to a location where a press machine can be found is also desired.